Development of a systems approach for the control of diseases in organic greenhouse crops

The study aimed to develop integrated crop management (ICM) systems in organic greenhouse production for improved control of tomato corky root rot (Pyrenochaeta lycopersici), tomato verticillium wilt (Verticillium albo-atrum), and cucumber powdery mildew (Podosphaera xanthii), compatible with and/or utilizing organic fertility management practices, while minimizing or eliminating permitted practices such as soil disinfection by steaming and foliar application of sulphur fungicide. Different concentrations of chitin (or chitosan -a water soluble form), fresh Brassica tissues, and cow manure based compost applied to soils infected with P. lycopersici alone and P. lycopersici plus V. albo-atrum reduced disease incidence and/or increased yield. However, efficacy differed between treatment types and concentrations. Compost or fresh Brassica tissue significantly increased soil microbial activity which may have increased competition and/or antagonism against soil pathogens, lowering disease incidence. Combining different treatments gave no synergistic or additive effects on incidence of both diseases, but the Brassica tissues plus chitosan combination improved yield. In tests of cultivar resistance/tolerance to the two pathogens, two "standard" cultivars were susceptible to both pathogens whilst the cherry type was tolerant to corky root rot, but not Verticillium. In soils infected with corky root rot only, grafting the cultivars onto a resistant root-stock effectively reduced disease incidence, but when infected with both pathogens, only one "standard" cultivar showed reduced disease incidence. In cucumbers, foliar application of chitosan reduced powdery mildew but Milsana® VP 2002 (a plant extract) was significantly better. Ampelomyces quisqualis and Pythium oligandrum (Biological Control Agents) were ineffective. There was no synergistic or additive effect detected with any combinations. Resistance/tolerance of cultivars significantly affected disease incidence. However, the more susceptible cultivar outyielded the tolerant one despite greater infection. Several components of an integrated strategy for control of diseases were identified with significant potential for development of more sustainable, organic protectedcropping systems.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Effectiveness of Pelvic Binders in Pre-Hospital Emergency Care: A Systematic Review of the Literature

Effectiveness of Pelvic Binders in Pre-Hospital Emergency Care: A Systematic Review of the Literatur

Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: a systematic literature review and meta-analyses

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Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: a systematic literature review and meta-analyses

Demand for organic foods is partially driven by consumers' perceptions that they are more nutritious. However, scientific opinion is divided on whether there are significant nutritional differences between organic and non-organic foods, and two recent reviews have concluded that there are no differences. In the present study, we carried out meta-analyses based on 343 peer-reviewed publications that indicate statistically significant and meaningful differences in composition between organic and non-organic crops/crop-based foods. Most importantly, the concentrations of a range of antioxidants such as polyphenolics were found to be substantially higher in organic crops/crop-based foods, with those of phenolic acids, flavanones, stilbenes, flavones, flavonols and anthocyanins being an estimated 19 (95% CI 5, 33)%, 69 (95% CI 13, 125)%, 28 (95% CI 12, 44)%, 26 (95% CI 3, 48)%, 50 (95% CI 28, 72)% and 51 (95% CI 17, 86)% higher, respectively. Many of these compounds have previously been linked to a reduced risk of chronic diseases, including CVD and neurodegenerative diseases and certain cancers, in dietary intervention and epidemiological studies. Additionally, the frequency of occurrence of pesticide residues was found to be four times higher in conventional crops, which also contained significantly higher concentrations of the toxic metal Cd. Significant differences were also detected for some other (e.g. minerals and vitamins) compounds. There is evidence that higher antioxidant concentrations and lower Cd concentrations are linked to specific agronomic practices (e.g. non-use of mineral N and P fertilisers, respectively) prescribed in organic farming systems. In conclusion, organic crops, on average, have higher concentrations of antioxidants, lower concentrations of Cd and a lower incidence of pesticide residues than the non-organic comparators across regions and production season